package com.nk;

import java.util.Arrays;
import java.util.Scanner;

/**
 * @ClassName Main2
 * @Description 描述
 * @Detail detail
 * @Author MyPC
 * @Date 2020/12/17
 * @Version 1.0
 */
public class Main2{
    public static void main(String[] args){
        Scanner scanner=new Scanner(System.in);
        while (scanner.hasNext()){
            String str = scanner.nextLine();
            StringBuilder sb=new StringBuilder();
            sb.append(str.charAt(0));
            for(int i=1;i<str.length();i++){
                boolean flag=false;
                for(int j=0;j<sb.length();j++){
                    if(str.charAt(i)==sb.charAt(j)){
                        flag=true;
                        break;
                    }
                }
                if(!flag){
                    sb.append(str.charAt(i));
                }
            }
            System.out.println(sb);
        }
    }
}